Does anyone have suggestions to improve the ride on my wife's 2005 300C with 30,000 miles?

I replaced the Contnentals at 15K because they were worn out with Goodyear Assured Tread. They lasted 20,000 miles. Probably due to running them at 30 PSI to make the ride as smooth as possible. The car now has Michilin Primacy MXV4 on it.

Generally, the ride is good, but you feel every bump in the road. That is the condition that I am trying to improve. This has been a problem since the Continentals were about 1/2 way gone.

Thoughts??

 

Well, since the car is 6 years old, an option is looking into replacing the shocks.
correct tire pressure should be between 32-35PSI's